One issue common to many data communication or storage systems is the corruption of data, for example, by noise in a communication channel or write/read processes in a storage system. One technique to remedy the data corruption is to use an error-correcting code (ECC) or forward error correction (FEC) code. Both ECC and FEC add redundant data or parity data to user data such that user data can be recovered by a receiver or reader even when a number of errors (up to the capability of the code being used) were introduced, for example, during the process of transmission or corruption on a storage.
A lot of different coding schemes have been developed over the years, for example, Hamming codes, Reed-Solomon codes, Turbo codes, etc. More recently, low density parity check (LDPC) codes have become widely used. All these codes, however, are computation complex and the techniques for using these codes are still in need of improvements.